Four-barrel governor carburetor



Jan. 30, 1962 J. E. FRANCIS 3,

FOUR-BARREL GOVERNOR CARBURETOR Filed June 25, 1956 2 Sheets-Sheet 1 IN VEN TOR.

JZJSEP/e 5/924 A/C/S Jan. 30, 1962 Filed June 25, 1956 2 SheecsSheet 2 154g 1 20 1 I 22 ZJLW i i 3 20 "W 9 ii /6 KC EZQ 2 INVENTOR. JZJSEPH 1 EPA/v05 Y 4 TTO/P/VE-Y 3,018,766 FUUR-BARREL GOVERNOR CARBURETOR Joseph E. Francis, Utica, Mich, assignor to Holley Carburetor Company, Van Dyke, Mich, a corporation of Michigan Fiied June 25', 1956, Ser. No. 593,459 23 Claims. (Cl. 123-119) This invention relates to governors for internal combustion engines, and more particularly to governors for internal combustion engines requiring dual or multistage carburetion.

Increasing horse power of automotive internal combustion engines has necessitated the use of two-stage carburetion as provided by the well known two or four barrel carburetor in which the throttle plate (or plates) controlling the flow of fuel-air mixture through the primary barrel (or barrels) is manually operated and the secondary throttle plate (or plates) is automatically opened against a spring tending to hold it closed by a suction device having a diaphragm actuated by primary and/or secondary venturi vacuum. The secondary barrels thus supplement the primary barrels when the capacity of the latter is exceeded.

In truck 'or other applications where it is desired to govern the speed of the engine and/or the speed of the vehicle, a second suction device actuated by primary 'venturi and/or manifold vacuum is provided to override the manual operation of and to close the primary throttle plate or plates, the intensity of the governing vacuum being controlled by a speed sensitive valve adapted to close an air bleed when the governed engine and/ or vehicle speed is reached.

It has been found, however, that such governing action in a two-stage carburetor is delayed as a result of the automatic secondary throttle plates not closing and opening at the same time as the primary throttle plates. This is because the secondary throttle plates open and close in accordance with vacuum developed at the primary and/ or secondary venturi. Since this vacuum does not change in direct proportion to the change in position of the primary throttle plates, the secondary throttle plates do not adjust in position to follow the primary throttle plates.

It is now proposed to provide a governor system for an internal combustion engine utilizing dual or multitage carburetion which will be free of the above objections to present governors. This is accomplished in the present embodiment of the invention by connecting the vacuum effective to positively close the primary throttle plates when governed speed is reached to the opposite side of a double acting suction device, which automatically opens the secondary throttle plates, in order to assist the spring or other resilient means in closing the secondary throttle plates in unison with the primary throttle plates when the engine or the vehicle reaches governed speed.

In the drawings:

FIGURE 1 is a side elevational view with portions thereof in cross section or a four-barrel carburetor provided with a governor embodying .the invention;

FIGURE 2 is a side elevational view, with portions thereof in cross section, taken on the plane of line 22 of FIGURE 1 and looking in the direction of the arrows;

FIGURE 3 is a cross sectional view taken on the plane of line 3-3 of FIGURE 1 and looking in the direction of the arrows;

FIGURE 4 is a bottom plan view taken on the plane of line 4-4 of FIGURE 1 and looking in the direction of the arrows; FIGURE 4 illustrates the manner in which the carburetor shown by FIGURE 1 is cut away to illustrate the primary and secondary throttle plates.

Referring now to FIGURE 1, a four-barrel carburetor in of the type referred to above and having an air intake is cut away as shown by FIGURE 4 to expose one of the primary barrels l4 and one of the secondary barrels 16. The primary barrel i4 is provided with a restriction or venturi i8 and a manually-operated throttle plate 20 mouted on the shaft 22 which extends through the other primary barrel in which is mounted a throttle plate identical to throttle plate 2%). The secondary barrel 16 is also provided with a venturi 24 and a throttle plate 26 mounted on the shaft 28 which extends through the other secondary barrel in which is mounted another secondary plate.

While a particular four-barrel carburetor is shown for purposes of illustration, it will be apparent that the invention is equally applicable to two-barrel or other multistage carburetors.

A suction device 30 commonly referred to as a governor diaphragm assembly is mounted on the boss 32 and gasket 33 extending from the carburetor throttle body 34. The assembly 30 includes a casting or other body 36 formed to provide recesses 38 and it The recess 40 is covered by means of a flexible diaphragm 42 which is secured to the body 36 by means of a cover member 44 formed to provide an air tight chamber 46 of which the flexible diaphragm 42 forms a wall. The cover member may be secured by any suitable means such as screws 47.

As shown by FIGURES 1 and 2, the diaphragm 4-2 has secured to the center thereof in the conventional manner a rod 48 passing through passage 5% in the body 36 and having a laterally extending end 52 pivotally secured to the lever 54 which is rigidly secured to the end 56 of the primary throttle shaft 22 extending into the chamber 38. The shaft 22 is mounted in the anti-friotion bearing 39, and a spring 41 is disposed between the bearing 39 and the steel and leather washers 43 and 45 to provide a seal. A tension spring 58 fixed between the adjustable pin 60 mounted in one of the holes 62 in the body 36 and the fixed pin 64 secured to the lever 54 tends to hold the primary throttle plate 20 in the open position so long as and to the degree that the usual foot throttle (not shown) is depressed. This is accomplished by a well known dog clutch arrangement, which is not shown since it does not constitute any part of the invention and which permits governor action described below to override the foot throttle control. A cover plate 66 secured by screws 68 against the gasket 71) seals the chamber 38 from atmosphere.

The orifice 72 at the primary venturi 13 and the orifice 74 below the primary throttle plate 20 are connected by means of the passages 76 and 78 having fixed restrictions 8 and 82 respectively with the passage 84 in the body member 36 and the passage 86 in the cover member 44 which lead to the chamber 46. A passage 88 connecting with passage 84 terminates in an opening in the body 36 adapted to receive a threaded fitting 9%.

Located at any desired position on the engine is a governor valve assembly 92 comprising a stationary housing 94 adapted to be mounted on the engine and containing a shaft 96 driven in any suitable manner in proportion to engine or vehicle speed. Mounted for rotation with the shaft 96 is a laterally extending sleeve 98 having a spring 1% mounted within the axial passage 02 in the sleeve in any suitable manner, such as in the internally threaded member 194, so that the spring 100 is adjustable axially by means of the adjustment screw 1% which is reached by removing the access screw 103. The other end of the spring ltlil is secured to the governor weight movable axially within the chamber 112 against the spring 1% and having at the free end thereof a valve 114 adapted to close the orifice 116 when the weight 110 is forced outwardly due to the rotation of the shaft 96 and the sleeve 98 in accordance with engine speed. The engine or vehicle speed at which the orifice 116 will be closed is dependent, of course, upon the adjustment of the spring 100. It is apparent, also, that some other governor valve structure may be employed.

Conduit 118 between the air intake 12 of the carburetor 1G and the housing 94 and conduit 122 between the housing 94 and the passage 88 in the body 36 are provided so that when the engine or vehicle is operating at a speed not sufficient to close the orifice 116, engine vacuum will draw clean air through the conduit 118, into the housing 94, through the orifice 116 and into the chamber 112, through the passage 192 and the axial passage 12% in the shaft 96 and thence through the conduit 122 to the governor diaphragm assembly 30. When the engine reaches governed speed, the orifice 116 is closed and the air bleed through conduit 122 is cut off. When this occurs, vacuum in the chamber 46 urges the diaphragm 42 downwardly, as in FIGURE 2, against the spring 58 to close the primary throttle plates 20.

A secondary throttle diaphragm assembly 124 i mounted at the opposite side of the throttle body 34. This assembly comprises a body 126 having a recess 128 closed to the atmosphere by a plate 130 secured by screws 132 and a recess 134 closed by a flexible diaphragm 136 which is secured to the body 126 by means of a cover 138 formed to provide oppositely disposed chambers 140 and 142 between which the flexible diaphragm 136 forms a movable wall. The chamber 142 contains a compression spring 144 positioned between the cover 138 and the rod 146, which is secured to the center of the diaphragm 136, so that the spring 144 urges the rod 146 upwardly to rotate the lever 148 secured rigidly to the secondary throttle shaft 28 counter-clockwise, as in FIGURE 3, and close the secondary throttle plates 26. A conduit 150 extending between the chamber 142 and the vacuum passages 152 and 154 opening to the primary and secondary venturis 18 and 24 enables primary and/ or secondary venturi vacuum to evacuate the chamber 142 and displace the diaphragm 136 downwardly, as in FIGURE 1, against the spring 144 to open the secondary throttle 26. The force of the spring 144 is selected so that the secondary throttle plate 26 will be open at any predetermined venturi vacuurn.

The structure described above, or its equivalents, is well known in the art, and proper governing action depends upon the particular complete closing of the throttle plates and 26 when the engine or vehicle has reached a predetermined governing speed so as to diminish or cut off the fiow of motive fluid to the engine. However, in the case of dual carburetion as described above, the automatic closing of the secondary throttle plates 26 lags behind that of the primary throttle plates 28, particularly at gov erned engine speeds at which the secondary plates 26 are not fully open so that linkage (not shown) usually eifective to positively close the secondary plates 26 with the primary plates 20 does not come into operation. While this is desirable or tolerable in the normal function of the dual carburetor whereby during acceleration additional fuel-air mixture is supplied to the engine when the primary barrels have reached their capacity, it is highly objectionable for the purposes of governing, since excessive motive fluid may continue to be supplied through the secondary barrels 16 for some period of time after the primary barrels 14 have been partially or fully closed, de-

pending upon engine load conditions. This causes huntphragm 136 to a position where the secondary throttle plates 26 are closed.

A spring loaded bleed valve assembly 158 may be insorted in the conduit 156 so that if the vacuum in the conduit 156 exceeds five inches of mercury, just for example, which is sufficient to actuate the diaphragm 136, the valve 160 will be opened against spring 162 to bleed air into the conduit 156. This prevents excessive vacuum in the chamber which may rupture the diaphragm 136 or jam the secondary throttle plates 26.

While but one modification of the invention is disclosed, it is to be understood that other modifications may be made and that no limitations not necessitated by the following claims are intended.

What I claim is:

l. A two-stage fuel control for an internal combustion engine, comprising primary and secondary valves for controlling the flow of separate charges of motive fluids to said engine and governor means for closing both of said valves when governed speed is reached.

2. A multi-stage fuel control for a vehicle internal combustion engine, comprising primary and secondary valves for controlling the flow of separate charges of motive fluid to said engine, and engine speed responsive governor means for closing both of said valves when governed engine speed is reached.

3. In a multi-stage fuel control for a vehicle internal combustion engine having primary and secondary valves for controlling the flow of separate charges of motive fluid to said engine, engine speed responsive governor means for closing both of said valves when governed engine speed is reached, said means being independent of any other connection between said valves.

4-. In a fuel control for an internal combustion engine having primary and secondary throttle valves for controlling the flow of separate charges of motive fluid to said engine, governor means for closing said primary throttle valve when said engine reaches a predetermined speed, means for opening said secondary throttle valve in accordance with engine requirements at any speed up to said predetermined speed, and means for positively closing said secondary throttle valve with said primary valve when said engine reaches said predetermined speed.

5. A compound carburetor, comprising at least one primary and one secondary throttle valve, said throttle valves being disposed in separate passages, said secondary throttle valve being normally closed by resilient means and being opened by a first two-way suction device actuated by vacuum proportional to engine air intake and said primary throttle valve being closed by a second suction device actuated by vacuum proportional to engine air intake at a predetermined engine speed, said first and second suction devices being connected by a vacuum conduit in a manner to assist said resilient means in closing said secondary throttle valve at the same time as said primary throttle valve when said engine reaches said predetermined engine speed.

6. A compound carburetor, comprising primary and secondary throttle valves disposed in separate passages, said secondary throttle valve being opened by a first twoway suction device actuated by vacuum proportional to engine air intake and said primary throttle valve being closed by a second suction device actuated by vacuum proportional to engine air intake at a predetermined engine speed, said first and second suction devices being connected by a vacuum conduit in a manner to close said secondary throttle valve at the same time as said primary throttle valve when said engine reaches said predetermined engine speed.

7. In an internal combustion engine, a primary intake passage having a throttle valve for controlling the flow of motive fluid therethrough, a secondary intake passage having a throttle valve therein, resilient means for normally holding said secondary throttle valve closed, a first suction device actuated by vacuum resulting from flow 'valve when said primary throttle valve is closed by said governor.

8. A vacuum governor for controlling the speed of an internal combustion engine having primary and secondary intake passages, each of said intake passages having a throttle valve for controlling the flow of motive fluid therethrough, comprising a first suction device actuated by vacuum incident to the operation of said engine for closing said primary throttle valve when said engine reaches governing speed, a second double acting suction device also actuated by vacuum incident to the operation of said engine for opening said secondary throttle valve, said secondary throttle valve being normally closed by resilient means opposing said second suction device, said second suction device being adapted by a common vacuum connection to said first suction device to close said secondary throttle valve simultaneously with said primary throttle valve when said engine reaches governing speed.

' 9. A vacuum governor for controlling the speed of an internal combustion engine supplied with fuel by a carburetor having primary and secondary intake passages, each of said intake passages having a throttle valve for controlling the flow of motive fluid therethrough, comprising a first suction device actuated by carburetor vacuum for closing said primary throttle valve when said engine reaches governing speed, a second double acting suction device actuated by carburetor vacuum for opening said secondary throttle valve, said second suction device being adapted by a vacuum connection to said first suct-ion device to close said secondary throttle valve simultaneously with said primary throttle valve when said engine reaches governing speed.

10. In a governed multi-stage carburetor having primary and secondary intake passages each controlled by a throttle valve, a first suction device actuated by vacuum in one of the intake passages to open the secondary throttle valve'in the secondary intake passage against resilient means operative to normally close said secondary throttle valve and a second suction device actuated by vacuum in the primary intake passage to close the primary throttle valve in the primary intake passage when said engine reaches governed speed, means also actuated by vacuum in said primary intake passages to assist said resilient means in closing said secondary throttle valve in unison with the closing of said primary throttle valve when said engine reaches governed speed.

11. A fuel control for an internal combustion engine, comprising primary and secondary intake passages each having a venturi, primary and secondary throttle valves in said intake passages for controlling the flow of motive fluid to said engine, resilient means for normally closing said secondary throttle valve in said secondary intake passage, means responsive to venturi vacuum for opening said secondary throttle valve against said resilient means, engine speed responsive means actuated by primary venturi vacuum for closing said primary throttle valve when said engine reaches governed speed, and means associated with said speed resonsive means for assisting said reslllent means in closing said secondary throttle valve simultaneously with said primary throttle valve at governed engine speed.

12. A fuel control for an internal combustion engine, comprising primary and secondary intake passages each having a venturi, primary and secondary throttle valves in said intake passages for controlling the flow of motive t 6 v fluid to said engine, resilient means for normally closing said secondary throttle valve in said secondary intake passage, means responsive to venturi vacuum for opening said secondary throttle valve against said resilient means, vehicle speed responsive means actuated by primary venturi vacuum for closing said primary throttle valve when said vehicle reaches governed speed, and means associated with said speed responsive means for assisting said resilient means in closing said secondary throttle valve simultaneously with said primary throttle valve at governed Vehicle speed.

13. A multi-stage fuel control for a vehicle internal combustion engine, comprising primary and secondary valves for controlling the flow of separate charges of motive fluid to said engine, and vehicle speed responsive governor means for closing both of said valves when governed engine or vehicle speed is reached.

14. In a multi-s-tage fuel control for a vehicle internal combustion engine having primary and secondary valves disposed in separate passages for controlling the flow of motive fluid to said engine, vehicle speed responsive governor means for closing both of said valves when governed vehicle speed is reached, said means being independent of any other connection between said valves.

15. In an internal combustion engine, a primary intake passage having a venturi and a throttle valve for controlling the flow of motive fluid therethrough, a secondary intake passage having a venturi and a throttle valve therein, resilient means for normally holding said secondary throttle valve closed, a first suction device actuated by venturi vacuum for opening said secondary throttle valve against said resilient means, a vacuum governor including a second suction device actuated by primary venturi vacuum for closing said primary throttle valve, 21 speed responsive bleed valve for rendering said second suction device inoperative at speeds below governed speed, and a vacuum connection between said first suction device and said second suction device to assist said resilient means in closing said secondary throttle valve when said primary throttle valve is closed by said governor.

16. A vacuum governor for controlling the speed of an internal combustion engine having primary and secondary intake passages, each of said intake passages having a venturi and a throttle valve for controlling the flow of motive fluid therethrough, comprising a first suction device actuated by primary venturi vacuum for closing said primary throttle valve when said engine reaches governing speed, a second double acting suction device actuated by primary and secondary venturi vacuum for opening said secondary throttle valve, said secondary throttle valve being normally closed by resilient means opposing said second suction device, said second suction device being adapted by its connection to said first suction device through a primary venturi vacuum conduit to close said secondary throttle valve simultaneously with said primary throttle valve when said engine reaches governing speed.

17. In a governed multi-stage carburetor having primary and secondary intake passages each controlled by a throttle valve, a first suction device actuated by vacuum in one of the intake passages to open the secondary throttle valve in the secondary intake passage against resilient means operative to normally close said secondary throttle valve and a second suction device actuated by vacuum in the primary intake passage modified by engine manifold vacuum to close the primary throttle valve in the primary intake passage when said engine reaches governed speed, means also actuated by said modified vacuum to assist said resilient means in closing said secondary throttle valve in unison with the closing of said primary throttle valve when said engine reaches governed speed.

18. A fuel control for an internal combustion engine, comprising primary and secondary intake passages, primary and secondary throttle valves in said intake passages for controlling the flow of motive fluid to said engine, resilient means for normally closing said secondary throttle valve in said secondary intake passage, means responsive to vacuum resulting from operation of said control for opening said secondary throttle valve against said resilient means, engine speed responsive means also actuated by said vacuum for closing said primary throttle valve when said engine reaches governed speed, and means associated with said speed responsive means for assisting said resilient means in closing said secondary throttle valve with said primary throttle valve at governed engine speed.

19. A fuel control for an internal combustion engine, comprising primary and secondary intake passages, primary and secondary throttle valves in said intake passages for controlling the flow of motive fluid to said engine, resilient means for normally closing said secondary throttle valve in said secondary intake passage, vacuum responsive means for opening said secondary throttle valve against said resilient means, vehicle speed responsive means actuated by vacuum above said primary throttle valve for closing said primary throttle valve when said vehicle reaches governed speed, and means associated with said speed responsive means for assisting said resilient means in closing said secondary throttle valve simultaneously with said primary throttle valve at governed vehicle speed.

20. An engine fuel control for a vehicle governed as to engine or road speed, comprising primary and secondary intake passages, primary and secondary throttle valves in said intake passages for controlling the flow of motive fluid to said engine, resilient means for normally closing said secondary throttle valve, vacuum responsive means for opening said secondary throttle valve against said resilient means, speed responsive means actuated by vacuum for closing said primary throttle valve when governed speed is reached, and means associated with said speed responsive means for assisting said resilient means in closing said secondary throttle valve simultaneously with said primary throttle valve at governed speed.

21. A charge forming device for an internal combustion engine, comprising primary and secondary induction conduit means communicating said pressure responsive mechanism with said primary induction passage to control the operation of said secondary throttle in accordance With the air flow through said primary induction passage, a governor device, means operatively interconnecting said governor device and said primary throttle valve, said governor device being adapted to move said primary throttle valve in a closed direction, and separate means operative during the primary throttle closing operation of said governor device to assist said biasing member in closing said secondary throttle.

22. A governor device for a multi-stage carburetor having a primary and a secondary induction passage with throttle valves therein adapted to control the flow of combustible mixtures to an internal combustion engine, comprising a venturi in said primary induction passage for causing a depression indicative of air flow through said primary induction passage, pressure responsive means operatively connected to said secondary throttle valve and said venturi in a manner so as to control the degree of opening of said secondary throttle in accordance with said venturi depression, and additional means operative upon attainment of governed speed for reducing the effect of said venturi depression on said pressure responsive means.

' 23. A multi-stage fuel control for an internal combustion engine, comprising a body, a primary and secondary induction passage including throttle valves therein formed within said body, means for controlling the ,degree'o'f opening of said primary throttle, means for creating a vacuum, the degree of which is indicative of engine operation, pressure responsive means operatively connected to said secondary throttle, conduit means for communicating said vacuum to said pressure responsive means so as to cause said pressure responsive means to open said secondary throttle in accordance with the pressure differential created by said vacuum, resilient means biasing said secondary throttle valve in the closing direction, a governor connected to said primary throttle and adapted to limit the degree to which said primary throttle can be opened, and additional means operative during governor operation for reducing said pressure difierential.

Ball Nov. 1, 1955 Sarto Nov. 1, 1955 

